Surgical instrument

ABSTRACT

A surgical instrument system for use in surgical procedures is disclosed. The surgical instrument system includes a guide assembly, a surgical tip assembly, and a drive unit. The guide assembly includes an elongated portion having a central axis of rotation, and a distal end that is positioned a radial distance away from the central axis. The surgical tip assembly may be attached to the guide assembly. The drive unit is coupled to the guide assembly for rotating the guide assembly and thereby rotating the surgical tip with respect to the central axis.

PRIORITY INFORMATION

[0001] The present application is a continuation of and claims priorityto International Application PCT/US00/12553 filed on May 9, 2000, whichdesignates the U.S. and in turn claims priority to U.S. ProvisionalPatent Application Ser. No. 60/133,407 filed on May 10, 1999.

BRIEF DESCRIPTION OF THE DRAWINGS

[0002] The following description may be further understood withreference to the accompanying drawings in which:

[0003]FIG. 1 shows a perspective view of a minimally invasive surgicalsystem including a surgical instrument of the present invention;

[0004]FIG. 2 shows a functional schematic diagram of the surgicaladaptor component of the system of FIG. 1;

[0005]FIG. 3 shows a functional schematic diagram of the instrumentinsert component of the system of FIG. 1;

[0006]FIG. 4 shows a perspective view of the surgical instrument insertcomponent of the system of FIG. 1;

[0007]FIG. 5 shows a perspective view of the coupler component of thesystem of FIG. 1;

[0008] FIGS. 6A-6B show perspective views of the end-effector componentof the system of FIG. 1;

[0009] FIGS. 7A-7C show exploded perspective views of the surgicalinstrument adaptor component of the system of FIG. 1; and

[0010]FIG. 8 shows a perspective view of the modular drive unit used inthe system of FIG. 1; and

[0011]FIG. 9 shows detailed drawings of the connector components of thesurgical adaptor used in the system of FIG. 1.

[0012] The drawings are for illustrative purposes only and are not toscale.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

[0013] The present invention provides an instrument system that may beused to perform minimally invasive surgery. An exemplary system of theinvention is actuated by a flexible cable assembly as shown in FIGS.1-9. Generally, the cable assembly is in the form of an array, and isremovably attached to an actuation drive unit. The actuation drive unitis remote from the operative site and is preferably positioned adistance away from the sterile field. The drive unit is electricallycontrolled by a computer system that is connected to a user interface.Commands issued at the user interface are translated by the computerinto electronically driven motion in the drive unit. The surgicalinstrument, which is tethered to the drive unit through its cableconnection, produces the desired motion.

[0014] The surgical instrument is generally composed of two components-asurgical adaptor and an instrument insert. The surgical adaptor is apassive mechanical device, driven by the attached cable array. Since thesurgical adaptor is detachable and relatively simple, it may be designedfor particular surgical applications, such as abdominal, cardiac,spinal, arthroscopic, sinus, neural, etc. The surgical insert couples tothe adaptor and essentially provides a means for exchanging theinstrument end-effectors. These inserts may include forceps, scissors,needle drivers, electrocautery, etc.

[0015] Referring specifically to FIG. 1, a surgical instrument system 10may preferably be used to perform minimally invasive procedures,although it is to be understood that the system may be used to performother procedures as well, such as open or endoscopic surgicalprocedures. The system 10 includes a surgeon's interface 11, computationsystem 12, drive unit 13 and a surgical instrument 14. The surgicalinstrument 14 is comprised of a surgical adaptor 15 and instrumentinsert 16. The system may be used by positioning the end effector 18 ofthe instrument insert 16, which is inserted through the surgical adaptor15. During use, a surgeon may manipulate the handle 30 of the surgeon'sinterface 11, to effect desired motion of the end effector 18 within thepatient. The movement of the handle 30 may be interpreted by thecomputation system 12 to enhance the movement of the end effector.

[0016] The system may also include an endoscope with a camera toremotely view the operative site. The camera may be mounted on thedistal end of the instrument insert, or may be positioned away from thesite to provide additional perspective on the surgical operation. Incertain situations, it may be desirable to provide the endoscope throughan opening other than the one used by the surgical adaptor 15.

[0017] The surgical instrument 14 is preferably mounted on a rigid post19, which is movably affixed to the surgical table 20. This preferablemounting scheme permits the instrument to remain fixed relative to thepatient if the table is repositioned. Although FIG. 1 depicts a singlesurgical instrument, it is to be understood that the system may have anynumber of instruments.

[0018] The surgical adaptor 15 of the surgical instrument 14 includestwo mechanical cable-in-conduit bundles 21 and 22. These cable bundles21 and 22 terminate at two connection modules 23 and 24, which removablyattach to the drive unit 13. Although two cable bundles are describedhere, it is to be understood that more or fewer cable bundles may beused. The drive unit 13 is preferably located outside the sterile field,although it may draped with a sterile barrier so that is may be operatedwithin the sterile field.

[0019] In the preferred method to setup the system, the surgicalinstrument 14 is inserted into the patient through an incision or anopening. The instrument 14 is then mounted to the rigid post 19 using amounting bracket 25. The cable bundles 21 and 22 are then passed awayfrom the operative area to the drive unit 13. The connection modules 23and 24 of the cable bundles 21 and 22 are then engaged onto theactuation unit 13. Instrument inserts 16 may then be passed through thesurgical adaptor 15. The surgical inserts 16 are coupled laterally withthe surgical adaptor 15 through the adaptor coupler 24.

[0020] The instrument 14 is controlled by the interface handle 30, whichmay be manipulated by the surgeon. Movement of the handle may produceproportional movement of the instrument 14 through the coordinatingaction of the computation system 12. In the typical case, movement of asingle hand controls movement of a single instrument. FIG. 1, shows asecond handle that may be employed to control an additional instrument.

[0021] The surgeon's interface 30 is in electrical communication withthe computation system 12, and the computation system 12 is inelectrical communication with the actuation unit 13. The actuation unit13, however, is in mechanical communication with the instrument 14. Themechanical communication with the instrument allows theelectromechanical components to be removed from the operative region,and preferably from the sterile field. The surgical instrument 14provides a number of independent motions, or degrees-of-freedom, to theend effector 18. These degrees-of-freedom are provided by both thesurgical adaptor 15 and the instrument insert 16.

[0022] The surgical adaptor 15, shown schematically in FIG. 2, providesthree degrees-of-freedom, which are achieved using a pivotal joint J1, alinear joint J2, and a rotary joint J3. From the mounting bracket 23,shown in schematically FIG. 2, a pivotal joint J1 pivots the surgicaladaptor assembly about a fixed axis 204. A first linear joint J2, movesthe guide tube 200 along an axis 201 defined by the tube. A rotary jointJ3 rotates the guide tube 200 its long axis 201. The guide tube 200 hasa bend 202 that causes the distal end of the tube to orbit the axis 201when the guide tube is rotated about its axis.

[0023] Through a combination of movements at joints J1-J3, the surgicaladaptor 15 can position its distal end 203 to any desired position inthree-dimensional space. By using only a single pivotal motion, theexternal motion of the surgical adaptor 15 is minimized. Furthermore,the pivotal axis 204 and the longitudinal axis 201 intersect at a fixedpoint 205. At this fixed point 205, the lateral motion of the guide tube200 is essentially zero.

[0024]FIG. 3 shows a schematic representation of the kinematics of theinstrument insert 16. The instrument insert 16 is placed through thesurgical adaptor 15, so that the movements of the insert are added tothose of the adaptor. The instrument insert 16 has two grips 304 and305, which are rotatably coupled to wrist link 303 by two rotary jointsJ6 and J7. The axes of joints J6 and J7 are essentially collinear. Thewrist link 303 is coupled to a flexible shaft 302 through a rotary jointJ5, whose axis is essentially orthogonal to the axes of joints J6 andJ7. The flexible shaft 302 is attached to a rigid shaft 301. The rigidshaft 301 is rotatably coupled by a joint J4 to the instrument insertbase 300. The axis of joint J4 is essentially co-axial with the rigidshaft 301.

[0025] The combination of joints J4-J7 allow the instrument insert 16 tobe actuated with four degrees-of-freedom. When coupled to the surgicaladaptor 16, the insert and adaptor provide the surgical instrument 14with seven degrees-of-freedom. Although four degrees-of-freedom aredescribed here for the insert 16, it is to be understood that greaterand fewer numbers of degrees-of-freedom are possible with differentinstrument inserts. For example, an energized insert with only onegripper may be useful for electro-surgery applications, while an insertwith an additional linear motion may provide stabling capability.

[0026] The instrument insert 16, shown in FIG. 4, is comprised of acoupler 401, a rigid stem 402, a flexible section 403 and an endeffector 404. The coupler 401 includes one or more wheels 405 whichlaterally engage wheels 726 of the coupler section 700 on the surgicaladaptor 15. The coupler 401 also includes an axial wheel 406, which alsoengages a wheel on the adaptor. The axial engagement wheel 406 is fixedto the rigid stem 402, and is used to rotate the end-effector axially atthe distal end of the flexible section.

[0027] A detail of the coupler assembly 401 is shown in FIG. 5. Eachwheel 405 of the coupler has two cables 500 and 501 that are affixed tothe wheel and wrapped about opposite sides at its base. The lower cable500 also rides over an idler pulley 502, which routes the cables towardthe center of the instrument stem 402. It is desirable to maintain thecables near the center of the instrument stem, since the cables will inaccordance with the rotation of the stem. The closer the cables are tothe central axis of stem the less disturbance motion on the cables. Thecables are then routed through plastic tubes 503 that are affixed to theproximal end of the rigid stem 402 and the distal end of the flexiblesection 403. The tubes maintain constant length pathways for the cablesas they move within the instrument stem.

[0028] The end effector, shown in FIGS. 6A and 6B, is comprised of fourmembers, a base 600, link 601, upper grip 602 and lower grip 603. Thebase 600 is affixed to the flexible section of the insert stem 403. Thelink 601 is rotatably connected to the base 600 about axis 604. Theupper and lower grips 602 and 603 are rotatably connected to the linkabout axis 605, where axis 605 is essentially perpendicular to axis 604.

[0029] Six cables 606-611, shown schematically in FIG. 6A, actuate thefour members 600-603 of the end effector. Cable 606 travels through theinsert stem and through a hole in the base 600, wraps on a roundedsurface on link 601, and then attaches on link 601. Tension on cable 606rotates the link 601, and attached upper and lower grips 602 and 603,about axis 604. Cable 607 provides the opposing action to cable 606, andgoes through the same routing pathway, but on the oppose side of theinsert.

[0030] Cables 608 and 610 also travel through the stem 403 and throughholes in the base 600. The cables 608 and 610 then pass between twofixed posts 612. These posts constrain the cables to pass substantiallythrough the axis 604, which defines rotation of the link 601. Thisconstruction essentially allows free rotation of the link 601 withminimal length changes in cables 608-611. In other words, the cables608-611, which actuate the grips 602 and 603, are essentially decoupledfrom the motion of link 601. Cables 608 and 610 pass over roundedsections and terminate on grips 602 and 603, respectively. Tension oncables 608 and 610 rotate grips 602 and 603 counter-clockwise about axis605. Finally, as shown in FIG. 6B, the cables 609 and 611 pass throughthe same routing pathway as cables 608 and 610, but on the oppose sideof the instrument. These cables 609 and 611 provide the clockwise motionto grips 602 and 603, respectively.

[0031] The instrument 16 slides through the guide tube 17 of the adaptor15, and laterally engages the adaptor coupler 24, as shown in FIGS.7A-7C. The adaptor coupler 24 is pivotally mounted 700 to the guide tubehousing 701. The guide tube housing 701 rotationally mounts the guidetube 17. The guide tube housing 701 is affixed to the linear slider 703,which travels along the linear stage 704. The linear stage 704 ispivotally mounted 705 on the base 706.

[0032] Cables, which enters the structure through conduits 707, actuatethe adaptor 15. The base pivotal joint 705 is control by two cables 708and 709, which pass over an idler pulley 711 and along opposingdirections on base capstan 710. The guide tube capstan 712, affixed tothe guide tube 17, and is actuated by cables 715 and 717, whichdifferentially rotates the guide tube. The axial capstan 713 isrotationally coupled to the guide tube and is actuated by cables 716 and718. The axial capstan 713 engages the axial engagement wheel 406 on theinstrument.

[0033] The cables 718 and 719, shown in FIG. 7C, actuate the linearslider 703. The cables enter the base 705 through conduits 706 andaround idler pulleys 720 and 721. Cable 718 passes freely through thelinear slider 703 and around the distal idler pulley 722 and back towardthe linear slider 703 onto which it terminates. The cable 719 terminateson the linear slider directly. The engagement wheels 726 located in theadaptor coupler 24 are actuated by cables, which enter the pivotaladaptor coupler 700 guided by idler pulleys 725.

[0034] All of the cables in their individual conduits are collected intotwo bundles 21 that exit the adaptor. These cable bundles terminate onconnection modules 22, which are shown in FIG. 8, and removably attachto the motor drive unit. The connection module 22 contains a row ofrotatable wheels 900, which engage matching wheels 800 located on themotor drive unit. As shown in FIG. 9, each wheel 900 actuates two cables901 and 902, which wrap about the circumference in opposing directions.An idler pulley 903 aligns one of the cables 902, so that both cables901 and 902 are in parallel and close together, so that they may beeasily fitted into the cable bundle 21.

[0035] The connection modules 22 removably attach to the motor driveunit 13. Each wheel of the connection module matches, and isindividually actuated by, the corresponding motor drive wheel 800.Notice that the square key 801 on the motor drive wheel matches thedetent in the connection module wheel. Each motor drive wheel is fittedto the axle of an electrical motor 802.

[0036] With the instrument insert coupled to the surgical adaptor andthe connection module fitted to the drive unit, the transmission allowseach motor 802 to actuate a single degree-of-freedom in either theadaptor or the insert. The mechanical assembly thus allows decoupledmotion for each degree of freedom. The complete system provides a fullseven degrees-of-freedom of motion for the surgical instrument withinthe body. These degrees-of-freedom include three translational movementsin three-dimensional space, three rotational movements allowingarbitrary orientation, and a single grip degree-of-freedom.

[0037] It is contemplated that various changes and modifications may bemade to the drive unit, cable assembly, surgical adaptor or instrumentinsert without departing from the spirit and scope of the invention asdefine by the following claims and their equivalents.

What is claimed is:
 1. A surgical instrument system for use in surgicalprocedures, said surgical instrument system including: a guide assemblyincluding an elongated portion having a central axis of rotation, and adistal end that is positioned a radial distance away from the centralaxis; a surgical tip assembly that may be attached to said guideassembly; and a drive unit coupled to said guide assembly for rotatingsaid guide assembly and thereby rotating said surgical tip with respectto the central axis.
 2. The surgical system as claimed in claim 1 ,wherein said guide assembly includes a guide tube that is curved at itsdistal end.
 3. The surgical system as claimed in claim 2 , wherein saidsurgical tip assembly is at least partially insertable into said guidetube.
 4. The surgical system as claimed in claim 1 , wherein saidsurgical tip provides at least three degrees of freedom.
 5. The surgicalsys tem as claimed in claim 1 , wherein said guide assembly and said tipassembly are coupled to a drive unit.
 6. The surgical system as claimedin claim 1 , wherein said surgical tip assembly includes an end effectorhaving opposing grip portions.
 7. A surgical instrument system for usein surgical procedures, said surgical instrument system including: aguide assembly that may be positioned in a surgical environment, saidguide assembly including a proximal end and a distal end, and includinga central opening along a longitudinal length of said guide assembly,said guide assembly being adapted for insertion into a patient and beingadapted for rotation about a longitudinal axis of said guide assemblywhen inserted into the patient; an end effector that may used insurgical procedures, and may be received by said proximal end of saidguide assembly, passed through said central opening, and to said distalend of said guide assembly within a patient; and a drive unit coupled tosaid surgical tip assembly for manipulating said surgical tip assemblywithin the patient.
 8. The surgical system as claimed in claim 7 ,wherein said drive unit is further coupled to said guide assembly forrotating said guide assembly and thereby rotating said end effectorwithin the patient.
 9. The surgical system as claimed in claim 7 ,wherein said guide assembly includes a guide tube that is curved at itsdistal end.
 10. The surgical system as claimed in claim 9 , wherein saidend effector is at least partially insertable into said guide tube. 11.The surgical system as claimed in claim 7 , wherein said end effectorprovides at least three degrees of freedom of movement within thepatient.
 12. The surgical system as claimed in claim 11 , wherein saidend effector portion includes two opposing gripper portions for use insurgical procedures.
 13. The surgical system as claimed in claim 7 ,wherein said drive unit is coupled to a computer processing unit, andwherein said drive unit is adapted to control the movement of said endeffector responsive to an automated procedure stored in said computerprocessing unit.
 14. The surgical system as claimed in claim 7 , whereinsaid drive unit is detachably coupled to said end effector.
 15. Thesurgical system as claimed in claim 7 , wherein said drive unit isdetachably coupled to said guide assembly.
 16. The surgical system asclaimed in claim 7 , wherein said drive unit is further coupled to saidguide assembly for rotating said guide assembly and thereby rotatingsaid end effector within the patient, and for sliding said guideassembly along a linear path with respect to the surgical environment.17. A surgical instrument for use in surgical procedures, said surgicalinstrument comprising: a distal end that is adapted to be inserted intoa patient during surgery; a proximal end that is adapted to remainoutside of the patient during surgery; a plurality of link memberscoupled to one another via a plurality of joints that are interposedbetween adjacent link members, some of said link members being locatedat the distal end of the instrument, said instrument providing at leastfive degrees of freedom of movement of said distal portion of saidinstrument inside of the patient; and drive means for effecting movementof said plurality of said link members about said plurality of joints.18. A surgical instrument for use in surgical procedures, said surgicalinstrument comprising: a guide assembly including a proximal end and adistal end that is adapted to be inserted into a patient, said guideassembly being adapted to rotate with respect to a longitudinal axisthereof; an end effector for use during surgical procedures, said endeffector being separable from and insertable into a patient through saidguide assembly; and actuation means for effecting movement of said endeffector.
 19. A surgical instrument as claimed in claim 18 , whereinsaid end effector provides at least three degrees of freedom ofmovement.
 20. A surgical instrument as claimed in claim 18 , whereinsaid end effector provides at least four degrees of freedom of movement.21. A surgical instrument for use in surgical procedures, said surgicalinstrument including a proximal end and a distal end and comprising: anend effector at the distal end of said surgical instrument, said endeffector for use within a patient's body during surgical procedures; aflexible intermediate portion extending from said distal end to saidproximal end; and a coupling assembly at the proximal end for securingsaid surgical instrument to an actuation unit within a surgicalenvironment.
 22. A method of manipulating a surgical instrument, saidmethod comprising the steps of: inserting a distal portion of a surgicalguide assembly into a patient; removably securing the surgical guideassembly in a surgical environment; inserting a surgical tip assemblythrough the guide assembly; and actuating a drive unit to effect themanipulating the position of the surgical tip assembly within thepatient.
 23. The method as claimed in claim 22 , wherein said methodfurther includes the step of receiving input signals from a user, andsaid step of manipulating the position of the surgical tip assembly isresponsive to the input signals.
 24. The method as claimed in claim 22 ,wherein said method further includes the step of manipulating theposition of the guide assembly.
 25. The method as claimed in claim 22 ,wherein said surgical instrument tip provides at least three degrees offreedom.